Coin in the context of "Money supply"

Lavrio, Lavrion or Laurium (Greek: Λαύριο; Ancient Greek: Λαύρειον (later Λαύριον); from Middle Ages until 1908: Εργαστήρια Ergastiria) is a town in southeastern part of Attica, Greece. It is part of Athens metropolitan area and the seat of the municipality of Lavreotiki. Laurium was famous in Classical antiquity for its silver mines, which was one of the chief sources of revenue of the Athenian state. The metallic silver was mainly used for coinage. The Archaeological Museum of Lavrion shows much of the story of these mines.

It is located about 60 km SE of Athens city center, SE of Keratea and N of Cape Sounio. Laurium is situated on a bay overlooking the island of Makronisos (ancient times: Helena) in the east. The port is in the middle and gridded streets cover the residential area of Lavrio. GR-89 runs through Lavrio and ends south in Sounio.

Money is any item or verifiable record that is generally accepted as payment for goods and services and repayment of debts, such as taxes, in a particular country or socio-economic context. The primary functions which distinguish money are: medium of exchange, a unit of account, a store of value and sometimes, a standard of deferred payment.

Money was historically an emergent market phenomenon that possessed intrinsic value as a commodity; nearly all contemporary money systems are based on unbacked fiat money without use value. Its value is consequently derived by social convention, having been declared by a government or regulatory entity to be legal tender; that is, it must be accepted as a form of payment within the boundaries of the country, for "all debts, public and private", in the case of the United States dollar.

A currency is a standardization of money in any form, in use or circulation as a medium of exchange, for example banknotes, coins,electronic balances in bank accounts, and central bank digital currencies (CBDCs).A more general definition is that a currency is a system of money in common use within a specific environment over time, especially for people in a nation state. Under this definition, the Pound sterling (£), euro (€), Japanese yen (¥), and U.S. dollars (US$) are examples of (government-issued) fiat currencies. Currencies may act as stores of value and be traded between nations in foreign exchange markets, which determine the relative values of the different currencies. Currencies in this sense are either chosen by users or decreed by governments, and each type has limited boundaries of acceptance; i.e., legal tender laws may require a particular unit of account for payments to government agencies.

Other definitions of the term currency appear in the respective synonymous articles: banknote, coin, and money. This article uses the definition which focuses on the currency systems of countries (fiat currencies).

Silver coins are one of the oldest mass-produced form of coinage. Silver has been used as a coinage metal since the times of the Greeks; their silver drachmas were popular trade coins. The ancient Persians used silver coins between 612–330 BC. Before 1797, British pennies were made of silver.

As with all collectible coins, many factors determine the value of a silver coin, such as its rarity, demand, condition and the number originally minted. Ancient silver coins coveted by collectors include the Denarius and Miliarense, while more recent collectible silver coins include the Morgan Dollar and the Spanish Milled Dollar.

The antoninianus or pre-reform radiate was a coin used during the Roman Empire thought to have been valued at 2 denarii. It was initially silver, but was slowly debased to bronze with a minimal silver content. The coin was introduced by Caracalla in early 215 AD. It was silver, similar to the denarius, except that it was slightly larger and featured the emperor wearing a radiate crown, indicating it was a double denomination. Antoniniani depicting women (usually the emperor's wife) featured the bust resting upon a crescent moon.

Even at its introduction, the silver content of the antoninianus was only equal to 1.5 denarii. This created inflation: people rapidly hoarded the denarii (Gresham's law), while both buyers and sellers recognized the new coin had a lower intrinsic value and elevated their prices to compensate. Silver bullion supplies began running short because the Roman Empire was no longer conquering new territory, the Iberian silver mines had been exhausted, and a series of soldier emperors and usurpers needed coin to pay their troops and buy their loyalty. Each new issue of the antoninianus thus had less silver in it than the last, and thus contributed to ever-increasing inflation.

The as (pl.: assēs), occasionally assarius (pl.: assarii; Ancient Greek: ἀσσάριον, romanized: assárion), was a bronze, and later copper, coin used during the Roman Republic and Roman Empire.

Copper is a chemical element; it has symbol Cu (from Latin cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.

Copper is one of the few native metals, meaning metals that occur naturally in a directly usable, unalloyed metallic form. This led to very early human use in several regions, from c. 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, c. 5000 BC; the first metal to be cast into a shape in a mold, c. 4000 BC; and the first metal to be purposely alloyed with another metal, tin, to create bronze, c. 3500 BC.

Byzantine currency, money used in the Eastern Roman Empire after the fall of the West, consisted of mainly two types of coins: gold solidi and hyperpyra and a variety of clearly valued bronze coins. By the 15th century, the currency was issued only in debased silver stavrata and minor copper coins with no gold issue. The Byzantine Empire established and operated several mints throughout its history. Aside from the main metropolitan mint in the capital, Constantinople, a varying number of provincial mints were also established in other urban centres, especially during the 6th century.

Most provincial mints except for Syracuse were closed or lost to Arab Muslim invasions in the Mediterranean Region by the mid-7th century onwards. After the loss of Syracuse in 878, Constantinople became the sole mint for gold and silver coinage until the late 11th century, when major provincial mints began to re-appear. Many mints, both imperial and, as the Byzantine Empire fragmented, belonging to autonomous local rulers, were operated in the 12th to 14th centuries. Constantinople and Trebizond, capital of the independent Empire of Trebizond (1204–1461), survived until the invasion of Anatolia by the Ottoman Turks in the mid-15th century.